1 files changed, 60 insertions, 0 deletions
diff --git a/devtools/client/inspector/markup/views/root-container.js b/devtools/client/inspector/markup/views/root-container.js
new file mode 100644
index 0000000000..8b34b85843
--- /dev/null
+++ b/devtools/client/inspector/markup/views/root-container.js
@@ -0,0 +1,60 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+/**
+ * Dummy container node used for the root document element.
+ */
+function RootContainer(markupView, node) {
+  this.doc = markupView.doc;
+  this.elt = this.doc.createElement("ul");
+  // Root container has tree semantics for accessibility.
+  this.elt.setAttribute("role", "tree");
+  this.elt.setAttribute("tabindex", "0");
+  this.elt.setAttribute("aria-dropeffect", "none");
+  this.elt.container = this;
+  this.children = this.elt;
+  this.node = node;
+  this.toString = () => "[root container]";
+}
+
+RootContainer.prototype = {
+  hasChildren: true,
+  expanded: true,
+  update() {},
+  destroy() {},
+
+  /**
+   * If the node has children, return the list of containers for all these children.
+   * @return {Array} An array of child containers or null.
+   */
+  getChildContainers() {
+    return [...this.children.children]
+      .filter(node => node.container)
+      .map(node => node.container);
+  },
+
+  /**
+   * Set the expanded state of the container node.
+   * @param  {Boolean} value
+   */
+  setExpanded() {},
+
+  /**
+   * Set an appropriate role of the container's children node.
+   */
+  setChildrenRole() {},
+
+  /**
+   * Set an appropriate DOM tree depth level for a node and its subtree.
+   */
+  updateLevel() {},
+
+  isSlotted() {
+    return false;
+  },
+};
+
+module.exports = RootContainer;